Geophysical Survey, Magnetometry Survey at Foxbury, Land north of Carterton, Oxfordshire

The surveys were undertaken using five Foerster Ferex 4.035 sensors mounted at 1m intervals (1m traverse interval) onto a rigid frame. The frame was towed on a wheeled non-magnetic cart behind a quadbike. The system was programmed to take readings at a frequency of 300Hz (allowing for a 10-15cm sample interval) on roaming traverses (swaths) 5m apart. These readings were stored on an external weatherproof laptop and later downloaded for processing and interpretation. The system was linked to a Trimble R12 Real Time Kinetic (RTK) differential Global Positioning System (dGPS) outputting in NMEA mode to ensure a high positional accuracy for each data point. DATAMONITOR 4 (Institut Dr. Foerster GmbH & Co. KG) software was used to collect and export the data. The Anomaly GeoSurvey v1.11.11 (� 2018 Robbie Austrums) software package was used to process and export the data plots. Subsequent data interpretation and illustration work was undertaken using QGIS v3.28.5. Anomalies due to both historical and recent agricultural activity (ridge and furrow and modern ploughing, drainage, and boundary rationalisation), geological variation and modern activity have been identified. Several anomalies of uncertain origin have also been recorded which are most likely to have a modern, natural, or agricultural origin. However, due to the archaeological activity within the site and surrounding landscape, an archaeological origin cannot be discounted. In addition, three areas of clear archaeological activity have been identified in the centre and south-east of the site. The activity recorded in the centre of the site correlates with the position of an enclosure recorded on the local historic environment record, although the survey has provided further detail on the extent and complexity of the remains. The two other areas of archaeological activity were not previously known and comprise enclosures and a possible trackway. Anomalies of probable and possible archaeological origin are also recorded in close proximity to the areas of archaeological activity, but these are more ephemeral and lack a clear pattern or morphology that would allow for a more confident archaeological interpretation. Based on the clear and obvious responses from the archaeological features it is assessed that the survey has provided a good indication of the archaeological potential of the site and the likely extent of the archaeological remains. Consequently, based solely on the results of the survey, the archaeological potential of the site is assessed as low but locally moderate to high in and around the clearly defined areas of archaeological activity.